Previous studies have established a direct association between chronic kidney disease (CKD) and cardiovascular (CV) mortality and morbidity. Evidence suggests that patients with CKD have an increased risk for myocardial infarction, heart failure, stroke, and mortality. “However, there is a paucity of data that helps identify those patients with kidney disease who are at an increased CV risk,” explains Horng H Chen, MD.

To better understand the connection between CKD and cardiovascular comorbidities, as well as the impact of high sensitivity troponin (hs-TnT) and brain natriuretic peptide (NT-proBNP) on this association, Dr. Chen and colleagues conducted a retrospective analysis of the Olmsted County Heart Function Study cohort and published their results in Mayo Clinic Proceedings. Both hs-TnT and NT-proBNP have been suspected to be telling biomarkers because both are cleared by the kidneys. The study authors assessed blood test data on hs-TnT and NT-proBNP to determine if they could be used to help identify patients with CKD who are at increased risk for adverse CV events.

Patients were classified based on their kidney function, and cardiac biomarker activation trends were characterized. Participants were organized into three groups dependent on estimated glomerular filtration rate (eGFR): normal renal function (eGFR≥90 mL/min/1.73 m2; Group I), mild renal insufficiency (eGFR 60-89 mL/min/1.73 m2; Group II), and CKD (eGFR<60 mL/min/1.73 m2; Group III). Dr. Chen and colleagues followed participants for a median of 10.2 years (interquartile range, 5.1-11.4 years). Compared with Group I, Group III participants were more likely to be older (75±9 years vs 58±9 years) and male (65.0% [82 of 126] vs 48.7% [399 of 819]).

Over 10.2 years follow-up, patients with CKD had an increased risk of heart attack (hazard ratio [HR], 1.95) and a composite of congestive heart failure, stroke, and all-cause mortality (HR, 1.38) when compared with patients without CKD. “Patients with NT-proBNP or hs-TnT in Group III were at greater risk of CV events without significant interactions between eGFR and levels of NT-proBNP and hs-TnT,” adds Dr. Chen.

The findings suggest that patients with high levels of hs-TnT or NT-proBNP are at a higher risk for adverse CV events (Table) regardless of their renal function. “Patients with CKD are at an increased risk for adverse CV events, including heart attack, heart failure, stroke, and death,”  Dr. Chen emphasizes. “Cardiac biomarkers like hs-TnT or NT-proBNP play a prognostic role in identifying individuals at high risk for adverse cardiac outcomes.” Overall, the evidence suggests that patients with CKD had a 38% higher risk of stroke than did patients in Group I (HR, 1.38).

“In this study, we demonstrated that NT-proBNP and hs-TnT have prognostic value regardless of patients’ kidney function,” says Dr. Chen. “Hence, these two biomarkers can be used to help clinicians identify patients with CKD who are at increased risk for adverse CV events.” Upon analyzing the optimal cutpoint for both biomarkers, both were at the third tertile. The optimal cutpoint for was 97.1 pg/mL for NT-proBNP and 3.8 ng/L for hs-TnT (Table).

Further research confirming that NT-proBNP and hs-TnT have prognostic value regardless of kidney function would help clinicians provide more precise care to patients with CKD who might be or are at an increased risk for adverse CV events and are candidates for aggressive CV risk strategies. “The next step in the research will involve clinical trials of patients with CKD who are identified to be at an increased CV risk using the NT-proBNP and hs-TnT biomarkers and randomizing them to aggressive risk modification strategies, to assess for improvement in long-term and short-term outcomes,” notes Dr. Chen.